00:01
So they give you the integral of the square root of x times natural log of x dx.
00:06
And they even tell you to let u equal natural log of x with dv equalling everything else, root x dx.
00:16
So what we have to do with this is find the derivative, du, which would be 1 over x dx.
00:23
And then let's think about this thing as x to the one -half power.
00:29
And when you're doing the integral, that's what we have to do, we have to add one to the exponent and then multiplied by the reciprocal of our new exponents.
00:41
Sorry, the reciprocal of our new exponent would be two -thirds.
00:46
There we go.
00:47
So part of integration by parts is i just tell people that go diagonally first.
00:54
So two -thirds x to the three -house power.
00:57
And then it's minus.
00:59
You multiply these two together.
01:03
So what are we looking at there? the integral of 1 over x...